Collapsible shipping case



Dec. 13, 1949 R. c. POTTS 2,491,206

COLLAPSIBLE SHIPPING CASE Filed April 26, 1944 5 Sheets-Sheet 1 FIGJ FIG. 2

R0) (.POTTS Dec. 13, 1949 R. c. PQTTS 2,491,206

COLLAPSIBLE SHIPPING CASE Filed April 26, 1944 5 Sheets-Sheet 2 FIG. 3A 65 R 0) c; POTTS Dec. 13, 1949 R. c. POTTS COLLAPSIBLE SHIPPING CASE 5. Sheets-Sheet 3 Filed April 26, 1944 gwwm R0) C POTTS Dec. 13, 1949 R. c. POTTS 2,491,206

COLLAPSIBLE SHIPPING CASE Filed April 26, 1944 5 Sheets-Sheet 4 502 306 FIG.9A V/////// 200 W 302 W6 306 F1610 FIG 11 206 20/ Slwuoniop I? YC. POTTS Dec. 13, 1949 R. c. PoTTs 2,491,206

COLLAPSIBLE SHIPPING CASE Filed April 26, 1944 FIG. 12

FIG. 13

5 Sheets-Sheet 5 ROY c. POTTS Patented Dec. 13, 1949 UNITED STATES PATENT OFFICE COLLAPSIBLE SHIPPING CASE Roy 0. Potts, Takoma Park, Md.

Application April 26, 1944, Serial No. 532,817

16 Claims. 1

It is an object of this invention to provide a collapsible box formed from a minimum number of individual parts, and involving a minimum number of die-cutting operations in the formation of the several parts.

It is a further object of this invention to provide, in a box of the class described, a wall formation whereby, without increasing the number of parts, the vertical strength of a given style of box may be increased by multiplying the wall thicknesses of one or more walls.

It is a further object of this invention to provide, in a box of the class described, a construction which lends itself to the formation of compartments by dividing the length of the interior of the box.

It is a further object of this invention to provide, in a box of the class described, a. construction of the corners which will permit collapsing the box without disassembly of the parts, and without unduly stressing any fibres at the corners.

It is a further object of this invention to provide a multi-compartment shipping case in which support is provided for the top and bottom closure flaps and in which the size of the'blanks may be reduced as the overall size of the shipping case increases.

These and other objects will be made clear from the following detailed description taken in connection with the annexed drawings, in which:

Fig. 1 is a plan view of one of the side wall forming blanks of my two compartment box;

Fig. 1A is a view similar to Fig. 1 but illustrating a form of blank which may be used when it is desired to have all transverse panels of double thickness;

Fig. 2 is a plan view of the blank forming one side wall and the top and bottom of said box;

. Fig. 2A shows a blank fulfilling the functions of the blank of Fig. 2 and intended for use with boxes of the type illustrated in Figs. 3A and A.

Fig. 3 is a perspective view illustrating the two compartment box formed from the blanks of Figs. 1 and 2;

Fig. 3A is a perspective view similar to Fig. 3, but showing a box formed by combining two blanks of the type shown in Fig. 1A with the blank shown in Fig. 2;

Fig. 4 is a plan view of the side wall forming I blankfor a single compartment box;

Fig. 4A shows a blank similar to that of Fig. 4, but having provision for double thickness end walls;

Fig. 5 is a perspective view of a single compartment box formed by combining the blanks of Figs. 2 and 4;

Fig. 5A is a perspective view similar to Fig. 5, but showing a box formed by combining the blank of Fig. 4A with the blank of Fig. 2;

Fig. 6 is a plan view of one of the side wall forming blanks of my three compartment box;

Fig. 7 is a plan view of one form of blank for forming an intermediate partition in my three compartment box;

Fig. 7A is a plan view of an alternate form of blank for performing the functions of the blank of Fig. 7;

Fig. 8 is a perspective view of my three com partment box formed by combining the blanks of Figs. 2, 6 and 7 with dotted outlines indicating the use of the blank of Fig. 7A;

Fig. 9 is a section through a typical corner illustrating my triple scored structure;

Fig. 9A shows the same structure expanded from to Fig. 9B shows the same structure collapsed from 90 to 0;

Fig. 10 illustrates an alternative form of corner structure applicable to any of Figs. 3, 5 and 8;

Fig. 11 illustrates still another alternative corner structure useable where die-cutting of 62 and 64 may not be wholly objectionable;

Fig. 12 is a top plan view of another form of two compartment carton;

Fig. 13 is a plan view of a single, two compartment box body forming blank;

Fig. 14 is a plan view of a blank for combination with the blank of Fig. 13 to double the thickness of certain walls thereof;

Fig. 15 is a top plan view of another form of two compartment box in which the size of the box forming blanks has been reduced;

Fig. 16 is a plan view of one of the box body forming blanks; and

Fig. 17 is a plan view of a second box body forming blank adapted to combination with the blank of Fig. 16.

In the design of shipping containers relatively thick and heavy materials are encountered whether the basic stock be corrugated board or solid fibre. In either case, but particularly when the material is solid fibre of around eighty points in caliper, die cutting is extremely difficult. It is one of my primary objectivesto design a box formed by combining two or more blanks in which each blank can be produced by simple scoring and severance without resort to any die cutting step. It is further to be noted that the elimination of die cutting eliminates all waste so that every square foot of board purchased by the box maker is utilized in the finished box.

In Figs. 1, 2 and 3. I show a side wall forming blank 50 having adjacent one end a score line 5i defining a fastening flap 52, a score line 53 defining, with score line 5|, a partition wall 5la, a score line 54 defining, with line 53, a side wall 530, and a score line 55 defining, with the score line 54, an end wall 54a, and with the free end 56 of the blank a front wall 55a which is double the width of the side wall 53a defined by lines 53 and 54.

Two identical blanks 50 are used to form all of the side walls of the box shown in Fig. 3, corresponding portions and score lines in the second blank are indicated by priming the reference numerals used in Fig. 1.

The box is completed and supplied with top and bottom closures by means of the blank 50 shown in Fig. 2. This blank 60 has a score line 5| defining a closure fiap 62 and a score line 53 defining another closure flap 64. Intermediate score lines BI and 63 are two additional score lines 65 and 55. These lines define between them a panel 51 which extends across the individual rear walls of both compartments. Score lines 5| and 65 define between them panel 68 which forms the top closure of the finished box while score lines 53 and 85 define between them a panel 69 which forms the bottom closure of the box. The box is finally closed by inserting flaps 52 and 64 between the panels 55a and 55a defined by score lines 55 and the end 56 of the blank 50 and score lines 55' and the end 55', of the blank 50', respectively. The construction just described, results in the formation of a two compartment box having its front and rear walls of double thickness, its end walls of single thickness, and its central partition of double thickness. The several parts may be securedtogether by gluing, stapling or other conventional means. A particular advantage of this box lies in the fact that it is collapsible from the condition illustrated in Fig. 3 by collapsing the corners formed by score lines 53 and 54' on one side and 55 and 5| on the other side and straightening the opposite corners to 180 relationship. It is, therefore, economically feasible to make a return shipment of the container which, when made of modern, rugged material is capable of repeated usage.

Referring now to Figs. 1A, 2 and 3A, I provide a blank l comprising a flap l2 and panels I4, l6, i8, 20 and 22 defined by score lines l3, l5, l1, l9 and 2!. Two such blanks, as shown in Fig. 3A, are combined with the blank of. Fig. 2 to form a two compartment box in which all the walls of each compartment are of double thickness. The second blank similar to Fig. 1A has its corresponding flap and panels identified as l2, l4, l6, i8, 20' and 22. It will be obvious that this structure must be restricted to boxes of limited size since otherwise blanks of the type illustrated in Fig. 1A would become so elongated as to become unwieldy, particularly when it is desired to apply the score lines continuously along an advancing web and to sever therefrom consecutive blanks along lines of severance transverse the score lines.

When the blank of Fig. 2A is substituted for the blank of Fig. 2 in the boxes shown in Figs. 3A and A, the fiaps 58L and SB'R enter spaces between plies l8 and 22' and I8 and 22, Fig. 3A, while auxiliary flaps GI'L and G'I'R enter the same spaces at the lower sides of the aforesaid plies. Applicability of the blank of Fig. 2A

to the form of Fig. 5A, or, for that matter, to the form of Fig. 8, if modified in accordance with Figs. 3A and 5A, is believed to be obvious.

The box illustrated in Fig. 5 is formed by combining the blank shown in Fig. 4 with the blank 60 shown in Fig. 2. the o change in blank 60 being to reduce its widthwise dimension from that suitable for the two-compartment box in Fig. 3 to that of .the single compartment box of Fig. 5. Accordingly, in Fig. 5, the same reference numerals are used with reference to the blank 60 as were used in Figs. 2 and 3.

In Fig. 4, I show a side wall forming blank 10 divided into panels ll. 12, 13, I4 and I5 by score lines ll, 12', I3 and 14', respectively. As shown in Fig. 5, panels H and 15 are superimposed to form a front wall or double thickness. while panels 12 and 14 form side walls of single thickness and panel 13 forms one thickness of the rear wall. The central panel 61 of the blank 60 is then suitably secured to the rear wall panel 13 to form a double thickness rear wall. Panels 68 and 59 of the blank 60 respectively form top and bottom closures and the box is completed by inserting fiaps 52 and 54 of the blank 50 between the panels H and of the blank 10.

Like the box of Fig. 3, the single compartment box is collapsible from the form illustrated in Fig. 5 by collapsing the corners defined by score lines H and 13' and expanding to 180 the corners defined by the score lines 12' and I4.

Obviously, the free ends of panels II and 15 of the blank 10 may be extended to form fastening flaps defined by score lines coincident with the free ends of panels II and 15 as illustrated. If'these are provided, the fastener flap of panel II would be secured to panel 14 and the fastener flap of panel 15 would be secured to panel 12. In order to simplify the description, detailed treatment of such fastener fiaps will be deferred until Figs. 10 and 11 are considered hereinafter.

Referring now to Figs. 2, 4A and 5A, I show in Fig. 4A a blank divided into seven panels 30, 32, 34, 36, 38, 40 and 42 by score lines 30', 32', 34', 36', 38 and 40'. This, as shown in Fig. 5A, is combined with the blank of Fig. 2 to form a single compartment box having all of its vertical walls of double thickness. In this structure panel 30 overlies panel 38 and panel 42 underlies panel 34. With this construction it will not usually be necessary to provide closure panels such as l2 in Fig. 1A or 52 in Fig. 1.

In Figs. 6 through 8, inclusive, I illustrate my three compartment box. This box is formed from a combination of two identical blanks of the form illustrated in Fig. 6, with a blank of the type illustrated in either Fig. 7 or Fig. 7A and the blank 60 illustrated in Fig. 2. As above noted, the blank 60 is modified only to the extent of changing its widthwise dimensions to conform to the greater over-all length of the three compartment box.

The blank illustrated in Fig. 6 is divided into a fastener flap 8| a partition panel 82, a rear wall panel 83, an end wall panel 84 and a front wall panel 85. These are defined by score lines 8|, 82', 83' and 84", respectively. The front wall panel 85 is of a length sufiicient to overly all three compartments. In Fig. 7, I show a blank 30 having a single central panel 9| with fastener flaps 92 and 93 at each side thereof, respectively defined by score lines 92' and 93.

In Fig. 7A, I show a blank I00 having a central 75 rear wall forming panel IOI defined by score lines I02 and I03 and having partition panels I02 and I03 at each side thereof. Panel I02 has at its free end a'fastener flap I04 defined by a score line I04 while panel I03 has at its free end a fastener flap I05 defined by score line I05.

When it is desired to have the partition walls defining the three compartments of single thickness only the blank 80 of Fig. 7 is utilized, but, if it is desired to have these partitions of double thickness, then the blank I of Fig. 7A is used.

In Fig. 8 I have shown in the assembly not only the blank 84 illustrated in Fig. 6, but an identical blank 84a in which all parts corresponding to blank 84 bear the same reference numerals but are distinguished by the addition of the symbol I a.

In final assembly, the fastener flap 8| of the blank 80 is bent at right angles to the panel 82 which latter forms a compartment defining partition. The panel 83 is bent at right angles to the panel 82 to form a rear wall. The panel 84 is bent at right angles to the panel 83 to form an end wall, and the panel 85 is bent at right angles to the panel 84 to form a front wall, the fastener flap 8| being glued, stapled or otherwise secured to the panel 85. The fastener flap 82 of the blank 80 is then secured to the panel 82 of the blank 80 and the panel 8I is bent at right angles theretoto form the rear wall of the central compartment. Duplicate blank 80a is then arranged to form the third compartment with its fastener flap 8Ia secured to the panel 85 of blank 80, its panel 82a forming a partition wall and having the fastener flap 83 of the blank 80 secured thereto. The panel 83a forms a rear wall, the panel 84a. an external end wall, and the panel 85a 9. front wall overlying the panel 85 toprovide a double thickness.

The blank 80 is then applied with its central panel 61 secured to each of the rear wall panels 83, 8I and 83a to provide a double thickness. Panel 68 of blank 80 forms a top closure and panel 88 a bottom closure. The box is completed by inserting flap 82 of panel 68 and flap 64 of panel 89 between the walls 85 and 85a.

When the blank. I00 of Fig. 7A is substituted for the blank 80 of Fig. '7, its central panel IOI coincides with the position shown in Fig. 8, its panel I02 overlies panel 82 with the fastener flap I04 secured to the panel 85. Panel I03 overlies panel 82a and its fastener fiap I is secured to thepanel 85. As above noted, this arrangement provides double thickness for the partition walls.

It will be obvious that the blank 80 of Fig. 7 may, for some purposes, usefully be combined with the boxes illustrated in Figs. 3, 5 and 8. When this is done, the central panel SI of the blank 90 will be stapled or otherwise secured to the singlethickness end walls of Figs. 3, 5 and 8. When this is done, flaps 82 and 83 may be folded inwardly at 90 to the panel 8I and thereby constitute supports for the closure panels 68 and 88 of Fig. 2.

As discussed in connection with Figs. 3 and 5, the three compartment box may be collapsed from the condition shown in Fig. 8 to a flattened condition and this may be done whether blank 80 or blank I00 be used in the central compartment.

It will be noted that the box shown in Fig. 8 may be increased in length by extending the front walls 85 and 85a, and additional compartments may be added by employing additional blanks I00 which are similarly applied between two adjacent partition walls.

Subject to the limitation of size discussed in connection with Figs. 1A and 3A, it is clear that the box illustrated in Figs. 6 through 8, inclusive, may have its exterior end walls of double thickness by the addition of a panel at the free end of panel in Fig. 6. This will not usually be necessary. When elongated boxes of this type are stacked one on the other, the greatest vertical load will be toward the center rather than the ends and, therefore, as a rule, the double thickness of the'interior partitions will provide sufllcient strength.

In the description heretofore, I have confined myself to the general features of construction and combination. Certain details of corner construction are, however, of great importance, and are equally applicable to all the forms already discussed, as well as to the particular corner flap arrangements which are described hereafter.

When superimposed boards of substantial caliper are folded through 180, the difference between the radius of fold of the outer board and that of the inner board is too great to be taken up by any stretch to be expected of the material here contemplated. The various blanks are originally formed in flattened condition. In practice they will usually be initially assembled in rectangular condition, and it will not be until the erected box is collapsed for return shipment that the extreme condition of 180 folding will be encountered. Micrometric exactness is not encountered in boxes of this class. Indeed, one of the merits of my design'is that reasonable inaccuracies are wholly permissible. Accordingly, and with easy commercial tolerances, the boxes may be erected from the fiat blanks without difliculty. When the erected box is to be collapsed, however, a new problem arises. One external corner must be opened from to while the adjacent corner must move from 90 to 0. Additional material is required in the corner moving from 90 to 0, while in'the adjacent corner which is actually straightened, there is an excess of materal. By the use of triple score lines, it is possible to use the excess of material at one corner to supplement the deficiency at the opposite corner. In this connection, it must be borne in mind that deficiencies occur at diagonally opposite corners, and that excesses similarly occur, that is, at diagonally opposite corners. There is, therefore, a, complementary condition at adjacent corners, that is, at the corners forming the extremities of any one wall.

The principle of triple scoring, which is analyzed in detail in the following discussion of Figs. 9, 9A and 93 requires for its perfection, that the material of two-ply walls be not mutually secured between adjacent corners. Triple scoring amounts simply to placing, on each side of the normal, corner-defining score line a similar, parallel score line. Each of the supplemental score lines should be somewhat spaced from the normal corner-definin score line, and the spacing should approximate, on eachside of the norma line, a distance equal to the combined thickness of the two plies. As will be made clear in discussing Figs. 10 and 11, the corner structure of my .boxes may be two-ply, even though one wall is single-ply and the adjacent wall is doubleply, There is, moreover, in the multi-compartmental structures, the occurrence of adjacent but oppositely facing corners. In this latter relationship, triple scoring is of importance in assuring complete collapsibility of the box, since it serves to minimize the possibility of rupturing the fibers on the outermost score line of a collapsing Monaco corner, even though one ply is not actually folded around the other.

In Fig. 9 I show a typical 90 corner structure involving an inner wall 300 and an outer wall 400. Wall 400 has a central score line 402 and supplementary score lines 404 and 406 at each side thereof. The inner wall 200 has a central score line 302 with supplementary score lines 004 and 306 at each side thereof. The central bending takes place along central score lines 302 and 402, and when the bend is a 90 score line 404 overlies score line 304 and score line 406 overlies score line 306.

In Fig. 9A the parts have been straightened from the 90 relationshipof Fig. 9 to the full 180. It is to be noted that while the central score lines 302 and 402 are mutually in alignment, score line 404 has moved slightly to the left of score line 304 and score line 406 has moved slightly to the right of score line 306. The distance by which the supplementary score lines are mutually oifset between the inner and outer plies represents the difference in the amount of material necessary to form the 90 fold in the outer ply over that needed to form the 90 fold in the inner ply. If, for any reason the outer ply were prevented from shifting relative to the inner ply. all of the score lines would remain in alignment but central score line 402 would be buckled outwardly away from score line 302.

In Fig. 93 I show the corner structure 001- lapsed from 90 to Central score lines 402 and 302 are still mutually superimposed but score lines 404 and 406 are respectively shifted inwardly from score lines 304 and 306. The shift is almost exactly the same as the outward shift- 8 separate the plies 204 and 206. A similar structure will. of course, occur at the opposite end of panel 206, but in this case the fastener flap would be an extension of the wall 204.

The structure described with respect to Fig. 11 has an advantage over that of Fig. 10 in that the assembly time will be reduced since it is not necessary to insert and remove spacing members. If, however, the construction of Fig. 11 be used it will be necessary to cut away the extremities of the flaps 62 and 64 of the blank 60 so as to clear the infolded fastener flaps such as 200 of Fig. 11. This introduces a die cutting step which, on certain grades and calipers of board may be undesirable.

The blanks of Figs. 13 and 14, when combined into the box of Fig. 12 are further combined with a blank of the type shown in Fig. 2. The blank of Fig. 13 comprises a closure flap 500 defined by a score line 50] and adjoining a partition panel 502. A score line 503 forms the other margin of the panel 502 and defines one side of a rear wall panel 504. A score line 505 forms the other margin of the panel 504, and defines one side of an end wall panel 506. A score line 501 forms the other margin of the end wall panel 506 and defines one side of a front wall panel 506 which has a width approximately double that of the end ing illustrated in Fig. 9A and if walls 300 and 400 are not rigidly secured to each other between adjacent corners, the excess of material illustrated in Fig. 9A will compensate for the deficiency of material illustrated in Fig. 9B.

It is not necessary, in all cases, that the inner ply 300 be given triple score lines and these are illustrated here primarily to demonstrate the presence of an excess of material in the outer ply when a ninety degree corner is straightened and the insufiiciency of material when such corner is collapsed.

Referring now to Figs. 10 and 11, I wish to point out that in Figs. 3, 5 and 8 I have indicated only that the two plies of the front wall are spaced to permit the insertion therebetween of the flaps 62 and 64 of the blank 60, and I have not indicated any particular structure for the corners of the front wall. Referring to the corner indicated at 55 in Fig. 3, 'II' in Figl 5, and 84' in Fig. 8, I

may complete the corner by providing a fastener flap 200 as shown in Fig. 10, stapled at 20! to the adjacent wall 202. In this case, the fastener flap 200 should be defined by triple score lines in the manner of Figs. 9, 9A and 93. During the assembly of the box, it will be necessary to insert spacers between walls 204 and 206 of Fig. 10 to wall panel 506. A score line 509 forms the other margin of the front wall panel 508 and defines one side of an end wall panel 5l0. A score line 5i i forms the other side of the end wall panel H0 and defines one margin of a front wall panel H2. The front wall panel 5l2 exceeds the width of the other front wall panel 502 by an amount equal approximately to the width of the closure flap 500.

The blank of Fig. 13 is formed into a two compartment box body by bending outwardly the closure flap 500 about the score line 50l to a position at right angles to the partition wall panel 502. The rear wall panel 504 is then bent to a position parallel to but in the opposite direction from the flap 500. The end wall panel 506,45 then bent at right angles to the rear wall panel 504 and the front wall panel 508 is bent at right angles to the end wall panel 506. The second end wall panel 5| 0 is then bent at right angles to the front wall panel 506, and the second rear wall panel 512 is bent at right angles to the second end wall panel 5i0 and, being of greater width than the rear wall panel 504, its extremity goes beyond the partition 502 and overlies the wall 604.

Corner closure flap 500 is stitched to front wall 508. The blank 60 shown in Fig. 2 is then applied across the rear wall panels 504 and SR with its central panel 61 overlying these rear wall panels. The panel 67 is stitched to panel 504 at 504'. It is stitched to panel 5l2 at 5I2', and a line of stitching 61 penetrates the panel 504, the overlying extremity of panel 5|2 and the panel 61 of blank 60.

The blank of Fig. 14 is then applied with panel 5 overlying panel 506 and'stitched thereto at 5". Panel 5l8 overlies panel 5i0 and is stitched thereto at 5l8'. Panel 5|6 overlies panel 506 and is spaced therefrom sufficiently to accommodate the thickness of the blank 60 (Fig. 2). The box is closed by folding inwardly the flaps 5i3, 5l5, 510 and 520. Panels 69 of blank 60 is folded across the bottom of the box and its flap 04 is tucked between the panels 506 and'5l6. The top of the box is closed by folding panel 68 across the 9 box and tucking its flap 52 between panels 588 and 518.

Figs. 15, 16 and 17 show a variation of the form illustrated in Figs. 12 through 14, in which the two-compartment box body is formed from two blanks instead of a single blank. This is advantageous where a relatively large box is desired, since it reduces the maximum size of blank to be handled. In Fig. 16 I show a blank for forming one compartment. This blank has a corner closure flap 540, adjoining a partition forming panel 542, the latter being defined at one side by a score line 540' and at the other side by a score line 542', which also defines one side of a rear wall panel 544. The other side of rear wall panel 544 is defined by a score line 544', which also defines one side of an end wall panel 546. The other side of end wall panel 546 is defined by a score line 548' which also defines a front wall panel 548. The front wall panel 548 exceeds the width of the rear wall panel 544 by an amount equal to the width of the corner fiap 540.

The blank of Fig. 1'? comprises a front wall panel 558, an end wall panel 552, and a rear wall panel 554 which exceeds the width of the front wall panel 550 by an amount approximating the width of the corner fiap 540 of the blank of Fig. 16.

The blanks of Fig. 16 and 17. are combined, as illustrated in Fig. 15. Corner flap 540 of the blank of Fig. 16 is bent at right angles to the partition panel 542. The rear wall panel 544 is then bent at right angles to panel 542, but in the opposite direction. End panel 546 is then bent at right angles to rear wall panel 544, and front wall panel 548 is bent at right angles to rear wall panel 548. The extra width of front wall panel 548 enables it to overlie corner flap 540. Front wall panel 550 of the blank of Fig. 1'7 is then placed between corner flap 540 and front wall panel 548, so that its free edge is flush with partition panel 542. End wall panel 552 is then bent at right angles to front wall panel 550, and rear wall panel 554 is bent at right angles to end wall panel 552. In this condition, the free margin of rear wall panel 554 overlies a portion of rear wall panel 544 of the blank of Fig. 16. The blank of Fig. 14 and the blank of Fig. 2 are then combined with the two-compartment inner structure, as shown in Fig. 15. Panel 5 of the blank of Fig. 14 overlies panel 548; panel 5l8 overlies and is spaced from panels 548 and 550; while panel 5|8 overlies panel 552. The central panel 51 of the blank 60 overlies rear panels 544- and 554. The stitching, as indicated, is identical 5 with that of Fig. l2. The method of closure is the same.

For simplicity of illustration, the thickness of the board of which my containers have been made is shown considerably exaggerated relative to the over-all dimensions of the containers. The actual thickness will vary between .045" and .080". When such thicknesses are contrasted with over-all box dimensions such, for example, as 12" x 12" x 24", it will be seen that what appears in the drawings to be a substantial distortion would, in practice, be entirely negligible.

I wish to make the point that all of the boxes.

herein disclosed are formed from absolutely rectangular blanks except when either the blank of Fig. 2A or that of Fig. 14 is used, and that the only treatment given to any of such blanks, other than mere cutting to size, is to apply a series of parallel score lines. I am not aware that heretofore anyone has produced boxes of the complex:

70 thickness of said wall.

ity of those herein disclosed without die cutting and/or the use of intersecting score lines in at least some of the blanks from which the ultimate I box is assembled.

The significance of the avoidance of die cutting and intersecting score lines lies in the fact that neither die cutting nor the application of intersecting score lines can be accomplished on shipping container board by means of any rotary machines now in existence, and, as a result, all

shipping containers, up to now, have been produced on flat bed machines at exhorbitant cost. Every element of every box within the scope of my invention can be produced by first trimming 15 the stock to a width equal to the length of the blank, passing the trimmed stock through sets of the proper width from the scored web. This is of the proper width from thescored web. This is not to say that my claims may not be infringed by a structure in which die cutting, or intersecting score lines may occur.

I claim:

1. A unitary collapsible shipping case having a body, the external walls of said body being of double thickness, the thicknesses of one side wall being spaced apart a distance equal to one thick ness of material, the outer thickness of the side wall opposite thereto being extended to form top and bottom closure panels for said box body and all said panels having flaps to enter said space, the

outer thickness of the end walls being extended to form flaps for supporting said top and bottom closure panels, score lines defining the corners of the inner thickness of said spaced-thickness wall.

and groups of three spaced score lines at the corners of the outer thickness of said wall. the central score line of each such group defining'the corner of the outer thickness of said wall.

2. A unitary collapsible shipping case having a 40 body partitioned into compartments, the external iii score lines at the corners of the outer thickness oi.

said wall, the central score line of each such group defining the corner of the outer thickness of said Wall.

3. A unitary collapsible shipping case having a 5 body partitioned into compartments, the external walls of said body being of double thickness, the thicknesses of one side wall being spaced apart a distance equal to one thickness of material, the outer thickness of the side wall opposite thereto being extended to form top and bottom closure lines defining the corners of the inner thickness of said spaced-thickness wall, and groups of three spaced score lines at the corners of the outer thickness of said wall, the central score line of each such group defining the corner of the outer 4. A unitary collapsible shipping case having a body partitioned into two compartments, the external walls of said body being of double, thickness, the thicknesses of one side wall being spaced apart a distance equal to one thickness of mamenace terial, the outer thickness of the side wall opposite thereto being extended to form top and bottom closure panels for said box body and said panels having flaps to enter said space. the inner thickness of said body and all partitions being formed from a single blank, score lines .defining the corners of the inner thickness of said spacedtliickness wall, and group of three spaced score lines at the corners of the outer thickness of said wall, the central score line of each such group defining the corner of the outer thickness of said wall.

5. A unitary collapsible shipping case having a body partitioned into two compartments, the external walls of said body being of double thickness, the thicknesses of one side wall being spaced apart a distance equal to one thickness of material, the outer thickness of the side wall opposite thereto being extended to form top and bottom closure panels for said box body and said panels having fiaps to enter said space, the outer thicknesses of the end walls being extended to form flaps for supporting said top and bottom closure panels, the inner thickness of said body and all partitions being formed from a single blank, score lines defining the corners of the inner thickness of said spaced-thickness wall, and groups of three spaced score lines at the corners of the outer thickness of said wall, the central score line of each such group defining the corner of the outer thickness of said wall.

6. A unitary collapsible two compartment box formed from two five-panel blanks and one threepanel blank, said five panel blanks being Joined to form a two compartment box body having three outer walls of double thickness and one of single thickness and a center partition of double thickness, said three panel blank being joined to said box body in such manner as to double the thickness of said single thickness wall and to provide top and bottom closure panels covering both compartments, score lines in their inner thickness of said walls defining the corners thereof, and groups of three score lines in the outer thickness of at least one of said walls adjacent the corners thereof, the central score line of each group of three overlying a score line in said inner thickness and defining corners of the outer thickness. 1

7. A unitary collapsible two compartment box formed from two five-panel blanks and one threepanel blank, said five-panel blanks being joined to form a two compartment box body having three outer walls of double thickness and one of single thickness and a center partition of double thickness, said three-panel blank being joined to said box body in such manner as to double the thickness of said single thickness wall and to provide top and bottom closure panels covering both compartments, there being lips at the free edges of said three-panel blank to enter a space between the double thickness of the wall of the box body opposite said single thickness wall, score lines in the inner thickness of said walls defining the corners thereof, and groups of three score lines in the outer thickness of at least one of said walls adjacent the corners thereof, the central score line of each group of three overlying a score line in said inner thickness and defining corners of the outer thickness.

8. In a box, a two-ply.wall having corners at by a single score line at the apex of the fold of the inner ply and by groups of three parallel score I lines at each corner of the outer ply, the central one of each such group overlying the score line of the inner ply. said plies being mutually free of each other between said corners.

9. A unitary collapsible shipping case having a body, the external walls of said body each comprising two plies, the plies of one of said walls being spaced apart'a distance equal tothe thickness of one ply and each comprising an integral extension of one of the piles of an adjacent wall, means securing the plies of each such adjacent wall against movement relative to one another, score lines in both of said spaced plies defining the intersections of said walls, and additional score lines in the outer plies of said walls parallel to and spaced on opposite sides of the intersection-deflning score lines of said outer plies, the score lines spaced on opposite sides of the overlying score lines providing corner fold lines respectively within or beyond the normal box corher as the corner structure is straightened or doubled, and the spaced apart plies of said one wall being free form attachment to one another throughout their areas and throughout'the region occupied by said score lines, whereby the inner and outer plies of said wall are free to shift with respect to one another as said box is collapsed.

10. A unitary box having a two-ply front wall, each ply of said front wall comprising an integral extension of an adjacent end wall, said two-ply front wall having corners at each end defined by a single score line at the apex of the fold of the inner ply and by groups of three score lines at each corner of the outer ply, the central one of each said group overlying the score line of the inner ply, said plies being free of one another between said corners; a rear wall opposite said front wall, said rear wall comprising two plies and top and bottom cover members adapted to cover the space between the front and rear walls, each of said cover members having a bendable fiap adapted to be inserted between the plies of said front wall, said cover members and said flaps comprising integral extensions of one of the plies of said rear wall.

11. A unitary box having a two-ply front wall, said plies being spaced apart and each being an integral extension of one ply of an adjacent twoply end wall, the plies of said end walls being secured together, the inner ply of said front wall being scored to define the corner folds thereof. the outer ply of said front wall also being scored to define the corner folds thereof, and the outer ply being additionally scored along two lines parallel to and spaced on opposite sides of each of the respective fold-defining score lines, whereby the corner structures may be straightened out or folded completely about one or the other of said additional score lines, the plies of said front wall being free from attachment to one another throughout their areas, and the distance between said additional score lines and the fold-defining score lines providing additional material sufficient to enable a relative lateral shift of the unattached inner and outer plies of said front wall as the box is collapsed; a two ply rear wall opposite said front wall and top and bottom cover members adapted to cover the space between the front and rear walls and each having a bendable flap adapted to be inserted between the plies of said front wall, said cover members comprising integral extensions of one of the plies of said rear wall.

12. A unitary collapsible shipping case having a body with at least two of the external walls of attachment to one another throughout their.

areas, there being score lines in both of said spaced plies defining the corner folds thereof, and additional score lines in the outer of said spaced plies parallel to and spaced on opposite sides of said corner-fold score lines whereby the corner structures of said two ply walls may be straightened out or folded completely, the dis tance between each of said additional score lines and said fold-defining score line being such as to permit a relative lateral shift of said spaced plies to accommodate changes in corner-to-corner length of the box front wall as the said box corners are either straightened out or folded completely as the box is collapsed.

13. A unitary box having a two-ply front wall, said plies being spaced apart and each being an integral extension of an adjacent end wall, the free end of each of said plies of said front wall being extended and secured to its abutting end wall, the inner ply of said front wall being scored to define the corner folds thereof, the outer ply of said front wall also being scored to define the corner folds thereof, and the outer ply being additionally scored along two lines parallel to and spaced on opposite sides of each of the respective fold-defining score lines, the distance between said spaced score lines and said fold-defining score lines providing for a relative shift of said spaced plies to permit folding of said corners upon one or the other of said spaced score lines as said corners are respectively straightened out or folded completely as the box is collapsed; twoply rear wall opposite said front wall and top and bottom cover members adapted to cover the space between the front and rear walls and each having a bendable flap adapted to be inserted between the plies of said front wall, said cover members comprising integral extensions of one of the plies of said rear wall.

14. A unitary collapsible box formed from the combination of one seven-panel blank and one three-panel blank, said seven-panel blank forming a rectangular box body with three double thickness walls, the thicknesses of the central one of said walls being free of attachment to one another throughout their respective areas, and one single thickness wall, said three-panel blank being secured to said box body in such a position as to double the thickness of said single thickness wall and to provide top and bottom closures for said box, there being flaps at the free edges of said three-panel blank to enter the space between the double thicknesses of that wall of said box body opposite said single thickness wall, score lines in the inner thickness of said double thickness walls defining the corners thereof, and groups of three score lines in the outer thickness of said double thickness walls adjacent the corners thereof, the central score line .of each group of three overlying a score line in said inner thickness and defining corners of the outer thickness when the box is set up.

15. A unitary, collapsible box formed from the combination of one seven-panel blank and one three-panel blank, said seven-panel blank forming a rectangular box body with three double thickness walls and one single thickness wall, the thicknesses of the central one of said double thickness walls being free from attachment to one another throughout their respective areas, said three-panel blank being secured to said box body in such a position as to double the thickness of said single thickness wall and to provide top and bottom closures for said box, score lines in the inner thickness of said double thickness walls defining the corners thereof, and groups of three score lines in the outer thickness of said double thickness walls adjacent the corners thereof, the central score line of each group of three overlying a score line in said inner thickness and defining the corners of the outer thickness when the box is set up.

16. A corner structure for a double walled box comprising a single score line defining the corner fold of the inner wall, a central score line in the outer wall overlying the score line of said inner wall and a pair of additional score lines in said outer wall parallel to and spaced on opposite sides of said overlying score line, whereby said corner structure may either be straightened to 180 degrees from degrees, or doubled from 90 degrees to 0 degrees, the score lines spaced on opposite sides of the central score line of the outer wall providing a corner fold line respectively within or beyond the normal box corner as the corner structure is straightened or doubled during collapsing of the box, and the distance between each of such corner fold lines and the normal box corner being substantially equal to the sum of the thicknesses of said inner and outer walls.

ROY C. POTTS.

REFERENCES CITED The following references are of record in the file of this patent: 

